Synthesis and Properties of the Bipolar Triphenylamine-benzimidazole Derivatives

A series of newly-developed bipolar triphenylamine benzimidazole derivatives, containing both hole-transporting and electron-transporting moieties, have been completely characterized by H-1 and C-13 NMR and HRMS, as well as their thermal, optical, and electrochemical properties. The results indicate that these compounds exhibit high fluorescence quantum yields, desirable HOMO levels and high thermal stabilities. Quantum chemical calculations were used to obtain the optimized ground-state geometries, spatial distributions of the HOMO, and the LUMO levels of these compounds. The agreement between experimental and calculated data suggests such compounds may have potential applications in organic light emitting diodes materials.